Racket



April 1o, 1934. J B, PANKER RACKET Filed June 22, 1952 INVENTOR;

n Harney.

Patented Apr. 10, 1934 i N ,1,954,327 t UNITED STATES PATENT OFFICEV` v` l @1,954,327 A H @aacxa'rvw l Bentlanker. Copenhagen,l applicati@ wie 2z, 1932. serial No. 618,619 l Q i In Germany June 24, 1931 f l Y f ,nonimaglot 27e-7s),

This inventQl relates to rackets "and *for its object to provide a cheap, strong and durablel perience to be unable to maintain the strings fully stretched for any considerable length of time;

The frames used for this purpose are usually made from wood bent into"the shape desired. They may also be made from metal or artificial substances, especially the so-called artificial resins.

The stretching of the strings forming the striking surface is rather complicated and very costly and, nevertheless, offers no safe guarantee for the elasticity of the strings, usually catgut strings, not failing during the course of time. The insertion of individual strings that have become slack is similarly a difficult matter.` It has also been attempted to use metal wires, but such wires, on the other hand, cannot be stretched land fastened in the frame with suiiicient tightness.

In my improved racket these drawbacks are avoided in that I manufacture the racket by imbedding a previously tightly stretched network in a frame consisting of a material, which during the imbedding of the net is rendered plastic and,

1, ,-d thus; encloses all the strings of the net, and when the frame after having received its shape has become hard, will secure the strings firmly in position. i v

i Especially great advantagesare attained, when the strings of the net `are metal wires, and the i latter combine a high elasticity with great i strength and, therefore, are not likely to break, l so that the racket will be verylong-lifed. The `racket can further be manufactured very cheaply,

" as it will be possible to use for the frames artificial wooden mass, artificial resins such as bakelite, galalith, ebonite or the like. i

On the drawing theinvention is illustrated by way of example:

Fig. 1 shows a frame with stretched metal-wire net, in top view.

Fig. 2 is a vertical cross-section, to a larger scale, of the matrix with the metal-wire net stretched therein.

` Fig. 3 shows a partial section of the frame with metal Wires imbedded therein, and i, Fig. 4 a partial section of the frame according to another construction.

According to invention the racket is manufactured by stretching metal wires 2 in a frame are pressed into the frames together with the 1, preferably of rectangular shape. By meansof tightening pegs 3 of similarnature as those used in musical instruments for` tuning the strings, the wires are stretched tightly, after `having been interwoven so as to form a stretched metal-wire so net.,` f

To `this metal-wire net `the racket frame 4 castor pressed, either, as shownbyffulljlines in Fig."1, in such a manner. that the metal wires2 run parallel orat rightangles rto the central axis of the frameonas shown by dotted lines,`in such' a manner that themetal" wires form angles of about with the central axis.

The racket frame may be made from artificial wood mass or from artificial resins such as bakelite, which becomes perfectlyhard by the pressure in the matrix and attains a strength equalling or even exceeding the strength of natural Wood. By

the pressure the material is compressed so firmly about the wires 2 that the latter, after the frame 75u has hardened, cannot be displaced any more. The racket frame may also be cast from materials suitable for the purpose. 1

Instead of using, as shown in Fig. 1, a special frame 1 for stretching out the wires 2, the wires 2 may be stretched, as shown in Fig. 2, in a. special i part of the matrix, in which the racket frame 4 is pressed.` Such a matrix is made in two parts, viz an outer annular part 5 fitted with holes through which the `wires 2 are entered. after which they are tightly stretched by means of pegs not shown, and of an inner part 51, 5,2, which also consists of two parts, and is applied to the wire net from above and from below. 'I'he matrix consists further of a top die and a bottom die 6 and 7, respectively, which can be pressed together for inst. by press stems `of a hydraulic press. After the pressing or casting,` the wire ends are cut off at the part 5.

In order to secure the wires 2 firmly in the frame the said Wires may be fitted with bends or windings 8 at the parts passing through the frame, as shown in Fig.` 3. The wires 2 may also, according to Fig. 4, be fastened on special pins 9 provided in the matrix 5, 6, 7, which pins Wires. The wires running in one of the directions may be wound about the crossing wires, in such a manner that eyes 10 are formed, which Vwill keep the wires in position. `The wires intersecting one another may also be interconnected -by means of welded joints 11. i

The wires 2 may consist of smooth piano wire of rustless steel or phosphor bronze, or else of twisted metal wires with a core of hemp.

It is especially advantageous to make the metal-Wire net from narrow thin metal bands Wound helically about a thin rod, in such a manner that a thin pipe is formed. The metal bands may for instance be 1./ 128 inch thick and 115 inch wide.

I claim: A l Y l l. Themethod of making rackets consisting in imbedding a tightly stretched net in a frame consisting of a material, which during the'imbedding is rendered plastic, and encloses all the strings of the net.

2. The method of making rackets consisting in imbedding a tightly stretched metal-wire net in a frame consisting of a material, which-during the imbedding is rendered plastic, and encloses all the strings of the net. .f

3. The method of making rackets consistingl in imbedding a tightly stretched net in a. frame consisting of a material, which during the imbedding is rendered plastic by heat, vand encloses all the stringszof the'net.

l4:. The method of making rackets consisting in` imbeddingfa tightly stretched net in a frame consisting of a material, which is rendered plasticby heat and by the application of pressure is caused to enclose all the strings of the net iirmly. A

5. The method of vmaking rackets consisting in imbedding a net, stretched tightly in a special stretching armature, in a frame consisting of a material, which during the mbedding is 'rendered plastic and encloses all the strings of the net.

6. The method of making rackets consisting in imbedding a net, stretched tightly in a matrix working as stretching armature, in a frame formed in the matrix by the use of heat and pressure of a material,l which during the forming is rendered plastic, the said frame enclosing tightly all the strings of the net.

7. The method of making rackets consisting in imbedding a tightly stretched net in a frame, consisting of a material, which during the imbedding is rendered plastic and encloses all the strings of the net, and where the strings of the net are interconnected in the parts thereof that are enclosed by the frame.

`8. A racket consisting of a net forming the striking surface and a cast frame carrying the net, said frame being cast on and about the edges of said net to rmly hold the same. A

9.*A racket consisting of a wire net forming the' striking surface and a cast `frame carrying the net, said frame being 'cast on and about the edges of said net to tightly grip the same.4

10. A racket, as claimed in claim 8, in which the edges of said net are bent to form anchors in the Yframe.

11. A racket, as claimed in claim 8, including fastening means for the net disposed inside said frame to secure the edges of said net to the frame.

BENT PANKER. 

